Roush Stage III Mustang.

Although his name will be on the car, Jack Roush says he had about as much to do with the development of the Roush Stage III Mustang as he did with the birth of his first child. "I was there for the engagement, for the romance," Roush says, but then his wife (in the case of the child) and his engineers (in the case of the car) did the heavy labor.

Although Roush is best known for his racing teams-campaigning multiple Winston Cup cars, dominating in the Trans-Am series and claming 10 consecutive class wins in the 24 Hours of Daytona-Roush's day job is operating Roush Industries, a major engineering supplier to Detroit's Big Three.

Conversion.

To convert a Mustang into a Stage III, Roush's engineers developed a new aluminum intake manifold that connects the 4.6-liter Ford V-8 engine to an Eaton Model 90 Gen 4 supercharger. With a special Roush high-volume 3-fuel system, the engine spins 360 horsepower at 5,250 rpm and 375 lb.-ft. of torque at 3,000 revs.

The package includes an aluminum flywheel (on cars with manual transmissions), Roush's own suspension components, Brembo or Roush-Alcon brakes, and 17- or 18-inch Roush aluminum wheels with BFGoodrich tires. Add to that re-bolstered and leather-covered seats, revised instrumentation, billet pedals, and a body kit with a rear wing and modified exhaust, with the customer's choice of side- or rear-exit pipes. The customer also can choose manual or automatic and coupe or convertible (which gets body-stiffening sub-frame connectors).

The "basic" package-a Mustang with the supercharged engine, Brembo brakes (with 13-inch front rotors; the Roush-Alcon version includes 14-inch front discs and 13-inch grooved rear rotors), 17-inch wheels and front facia-costs $39,500. A Rally package-for $44,050-adds the 18-inch wheels, modified suspension, billet pedals and gauges. But opt for the full Premium package and Roush promises that for $48,975 you get a car that will compete with a BMW M3 ($46,000), a Chevrolet Corvette Z06 ($48,000), a Porsche Boxster S ($50,200) or even a Dodge Viper ($70,000).

Premium III.

Roush's company says the Premium Stage III produces a 0-60 mph sprint in 4.9 seconds (5.3 with an automatic gearbox) and covers a quarter-mile in 12.7 seconds in excess of 109 miles per hour. The car stops from 60 miles per hour in 120 feet and turns 0.96-0.98g on the skidpad.

"Between a race car and a road car is a Roush car" is the tag line for Roush Performance Products, which introduced the car to the automotive media on the road course at Firebird International Raceway outside Phoenix, Arizona.

True OEM.

The Stage III was impressively powerful and fast, yet there was nothing brutal or harsh about its performance, nor was there any sense that the car had been cobbled together, which is not the case with many "tuner" cars. But don't mention that word around Roush's engineers. They are proud to point out that the Stage III Mustang is a true OEM vehicle that went through full certification trials. They are extremely proud that the car also meets federal drive-by noise limits, even when it wears side pipes.

While Roush is proud of his offspring, he won't plaster his name all over it. Roush badging will include an insignia stitched into the seatbacks and a small "Roush III" emblem on the back of the car, where it might be seen briefly before the car disappears toward the horizon.